Mere Christianity is a theological book written by C.S. Lewis and published in 1952. The book talks about Christianity, explaining the religion and dispelling any controversies. C.S. Lewis narrates the book and spends most of the story defending the Christian faith on an argument based on morality, a point which persuaded him from atheism to Christianity. His stance is of a moral law, a "rule about right and wrong" commonly known to all human beings. After providing reasons for his conversion to theism, Lewis goes over rival conceptions of God to Christianity. The story then explores the ethics resulting from Christian belief. Lewis describes the four virtues: prudence, justice, temperance, and fortitude. Lewis finally ends the book by emphasising his final point, which is that Christianity mandates that one "love your neighbor as yourself."
The book was written by the author to explain Christianity in its simple form and to dispel the controversies of Christianity. The book was also written so that the author could explain why and how he came to believe in Christianity and what he thinks about the religion itself.
The book was well received by critics and fans alike. In 2006, the book was placed third in Christianity Today's list of the most influential books amongst evangelicals since 1945. Also, Michael Fein of Central Virginia Community College, USA, noted that the book 'employs logical arguments that are eloquently expressed'.